One day in 1952, John W. Hetrick was driving with his wife and daughter in the front seat when he had to change his direction suddenly and brake quickly to avoid an obstacle. Instinctively, he and his wife put their arms out to protect their daughter in case of a crash. This event inspired him to provide automobiles with airbags to protect people during accidents. Hetrick had been an engineer in the US Navy during World War II. He recalled a compressed-air torpedo accidentally turning itself on, causing its canvas cover to shoot up into the air, 'quicker than a blink of an eye'. In 1952, Hetrick proposed using compressed air to inflate airbags rapidly during car crashes. He received a patent for this invention in 1953, but car manufacturers in the 1950s were more interested in style than safety. Later, consumers became more safety conscious and airbag technology improved. The first airbags were optional, but by the 1990s, they had become standard. Although airbags have saved thousands of lives, they are not always sufficient to prevent death and injury during crashes. Travellers must also wear seat belts, and automobiles must have dashboards made of soft materials and steering columns that can absorb energy during impact from car crashes.